Food packaging testing involves testing of any packaging material that contains food items. Food packaging testing helps manufacturers ensure that the packaging on their food items is functional, and of course, safe – for both people and the environment.

Migration testing is one method of food packaging testing which is used to evaluate the movement of chemicals in packaging materials into food. In this article, we’ll cover what migration testing is, the types of migration testing and when they are used, and challenges food manufacturers face during testing.

Key Takeaways

Migration testing in food packaging is a testing method that measures the transfer of chemicals from packaging into food.
Migration testing helps ensure compliance with international regulations and ensures the safety and quality of food products. This is particularly important for new, more sustainable packaging materials like biodegradable plastic.
There are two main types of migration testing: overall migration testing, which measures the total amount of substances transferred from packaging to food, and specific migration testing, which measures the amount of a single substance that is transferred.

What Is Migration Testing in Food Packaging?

Migration is the process by which chemicals are transferred from the food packaging (or other food contact materials, FCMs) to the food itself. Migration includes the transfer of chemicals from the packaging materials themselves, such as paper or plastics, but also includes the transfer of components added to the packaging, such as ink or adhesives. Generally, any chemicals that transfer and come into contact with food are known as food contact chemicals (FCCs).

There are a variety of reasons migration may occur. The main factors that affect migration include

Amount of time the food is in contact with the packaging
Chemical makeup of the food (e.g., acidic, dry)
Amount of surface area touching between the food and the packaging
Type of packaging materials and components
Temperature (e.g., refrigerated, frozen, room temperature)

Migration testing in food packaging is a testing method that measures the transfer of chemicals from packaging into food. The goal of migration testing is to determine whether chemicals were transferred from the packaging to food. Migration testing also ensures that if substances that pose health risks are transferred, the amount transferred is below the regulatory migration limits, or the maximum amount of a substance deemed to be safe.

Not only is migration testing in food packaging a key step in ensuring safe food products, but it also certifies that brands comply with international Food Contact Regulations, discussed below. Without migration testing, brands risk selling unsafe, non-compliant products to consumers, thus putting their reputation – not to mention their customers – at risk.

Migration testing can play a role in mitigating the migration of harmful chemicals from packaging into landfills and the environment by identifying potential risks early in the packaging development process. By ensuring that packaging materials are designed to minimize migration under realistic conditions, such as exposure to moisture or heat, it can reduce the likelihood of chemical leakage when these materials ultimately end up in landfills. This proactive approach not only enhances food safety but also contributes to environmental protection by curbing the release of harmful substances from discarded packaging into the ecosystem.

Importance of Migration Testing in Food Packaging

Some substances that migrate from food packaging can harm human health. For example, one 2009 study found that infant foods packaged in recycled paperboard boxes with paper liners contained levels of phthalates (a class of toxic chemicals) above the limits deemed safe by the European Commission. Migration testing helps ensure that transfer of hazardous substances is non-existent or below safe limits.

Migration testing allows manufacturers to ensure that their food products are not only safe, but that the food quality is not impacted by migration from the packaging. For example, even if migration occurs at safe amounts, the migration may still negatively affect the smell or flavor of the food.

Migration testing benefits manufacturers and distributors directly by helping avoid costly recalls and damage to brand reputation. In 2010, Kellogg had to recall around 28 million cereal boxes due to leaching of methylnaphthalene from the box’s paper lining into cereal. Several consumers reported illness after eating this contaminated cereal.

Additionally, many markets require migration testing before packaged food products can be sold. Migration testing is an important aspect of compliance, as there are several international regulations that mandate migration testing for any materials that come into contact with food.

Importance of Migration Testing for Sustainable Packaging

In the ever-evolving landscape of sustainable packaging, the significance of migration testing is more pronounced than ever before. As the industry introduces novel, eco-friendly materials and designs, the need to guarantee the safety and quality of food products contained in sustainable packaging has become paramount.

In the realm of sustainable packaging, there's a wave of innovation bringing new materials into the spotlight. These cutting-edge materials often emphasize eco-friendliness, from biodegradable plastics to plant-based alternatives. However, just because these materials are more eco-friendly than conventional packaging does not mean that they’re safer. Migration of chemicals can happen just as easily! Migration testing is a critical method of ensuring that new sustainable materials do not pose health risks to consumers.

One example of a more eco-friendly packaging option that may still pose a risk of chemical migration is biodegradable plastic packaging. While biodegradable plastics are designed to break down more easily in the environment, they often involve the use of chemical additives to achieve their properties. These additives, intended to expedite degradation, can sometimes leach into the packaged food, potentially raising concerns about chemical migration and its impact on food safety.

Is Migration Testing Required?

There are several regulations around the world that govern migration testing of food packaging. These apply to all types of food packaging, not just sustainable packaging, although there are some regulations that apply to specific types of packaging (like the EU’s regulations).

United States

The U.S. Food and Drug Administration has created several laws that govern any materials that come into contact with food (FCMs). The primary law is the Federal Food, Drug and Cosmetic Act, which requires FCMs to be safe for their intended use. The U.S. FDA’s Code of Federal Regulations (CFR) Title 21 lays out good manufacturing practice (GMP) for packaging food and creates limits for the safe amount of a substance that may migrate from packaging to food. The Threshold of Regulation (TOR) Rule allows the FDA to exempt some substances from regulation based either on the dietary exposure resulting from migration or the toxicity of the substance.

European Union

The main legislation governing food contact materials in the EU is Regulation (EC) No 1935/2004. This Regulation outlines GMP for any materials sold in the EU that touch food, including packaging. Article 3 of the regulation states that food contact materials cannot transfer substances to food at levels harmful to human health, or at levels high enough to bring about changes in the composition of food. In order to ensure compliance with this Regulation, manufacturers must undergo migration testing for all food packaging.

Regulation No 1935/2004 is the primary regulation governing food contact materials in the EU, although there are several regulations that cover specific food packaging materials. These include:

Ceramics: Directive 84/500/EEC
Regenerated cellulose film: Directive 2007/42/EC (Regenerated cellulose film packaging is a sustainable alternative made from cellulose derived from renewable sources like wood pulp or cotton. Its sustainability lies in its biodegradability and renewability, as it can be broken down by natural processes and is sourced from materials that can be replenished, reducing the environmental impact of packaging.)
Plastics: Regulation (EU) No 10/2011
Epoxy derivatives: Regulation (EC) No 1895/2005

Other Regulations

Other countries with food contact material regulations governing migration include, but are not limited to:

China: Food Safety Law of the People’s Republic of China
Japan: Food Sanitation Law Part II
South Korea: Food Sanitation Act, Chapter 3

Types of Migration Testing in Food Packaging

Testing is designed to measure the transfer of many different types of substances found in food packaging. Because migration of chemicals is an extremely complex process that depends on many variables, testing procedures vary based on a number of factors.

The type of migration testing depends on the type of packaging and its intended purposes. For example, plastic packaging on a frozen meal, which will be stored for long periods of time at low temperatures, may undergo slightly different migration testing than a plastic bag surrounding a loaf of bread, which will likely be stored at room temperature and eaten more quickly.

Testing also differs based on the type of food that will go inside that packaging. For example, alcoholic food items will react differently than acidic food items. Testing is designed to incorporate different variables including testing temperature, time, and other environmental conditions. Usually, the packaging is tested under a “worst-case” scenario designed to mimic the harshest conditions (for example, the highest temperatures) the product may face in real life. Once the packaging is exposed to these simulated conditions, the food is tested for the presence of migrated substances. Migration testing designed to measure sustainability factors, such as leaching into the environment from landfills, must also be designed with those conditions in mind.

Despite these many variations, there are two main types of migration testing in food packaging.

Overall migration testing

Overall migration testing ensures that the total amount of all substances that migrate from the packaging to the food is below the Overall Migration Limit (OML), an amount set by regulations in Europe, China, and South America. While US regulation does not set an OML, it does have similar regulation in place that measures the total substances transferred. OMLs are usually expressed as mg per food contact surface area (mg/dm2).

Specific migration testing

Specific migration testing ensures that the amount of a single, specific substance that migrates from the packaging to the food is below the Specific Migration Limit (SML) required for that substance. The SMLs are typically based on toxicological risk assessments that determine the maximum safe level of exposure to a substance. The allowable limits for specific substances are set in most food contact material regulations around the world. SMLs are typically measured in mg/kg of food.

Challenges of Migration Testing in Food Packaging

The main challenge in migration testing is accurately testing under the wide variety of real-world conditions the product may face. As mentioned above, the properties of food vary greatly, as do the conditions a product may face. Testing must be broad enough to accurately assess how migration may occur in every possible scenario. This is particularly difficult when taking landfills into consideration, as conditions may vary. It can be extremely hard to determine the right testing to assess how packaging will break down in the environment once it is disposed of.

In order to meet this challenge, many laboratories perform simulated testing with “food contact simulants,” rather than testing actual food products in the real world. However, the difficulty lies in properly simulating conditions for every different type of food product and packaging combination.

The efficacy of the test is determined by choosing the correct tests for the correct situations and materials. If the wrong parameters for testing are applied and the packaging is exposed to different conditions in the real world, testing may not accurately assess the true amount of migration that is happening once a product is sold. For example, if a plastic bag is tested only in low temperatures but is used in high temperatures in the real world, the testing may not catch migration that occurs at higher temperatures. This will pose a major health risk to consumers and place the company at risk of being penalized for breaking compliance.

Another higher-level challenge is that there are thousands of food contact chemicals that have not been reviewed by authorities. While this is not a challenge of migration testing specifically, it does raise concerns about migration from food packaging generally. For example, a 2017 paper found that companies may make decisions about the safety of some food contact chemicals without oversight from authorities. The same paper points out another challenge, that some migration limits for specific chemicals can’t actually be enforced because there are no appropriate methods to test for the presence of those chemicals in food.

Ultimately, the best way to address these challenges is to ensure that migration testing is performed by a trusted third-party laboratory that adheres to strict standards for selecting the appropriate testing protocols and utilizes a wide range of approved testing methods. A third-party laboratory can also help you identify what tests to perform based on your destination market.

About the Author:

David Evans is a freelance writer covering sustainability challenges and solutions. He writes to help companies and consumers understand the environmental and ethical challenges in products and their supply chains so we can find viable solutions for both. See more of David’s writing at: Plastic.Education